Thanks to the phenomenal quality and quantity of points generated, reaching up to 2 000 000 per second, recent 3D scans are among the most proficient measuring tools available on the market. How does it work? How can we actually use them? What about their applications? As the expert is never the device, but the operator, the use of this technology has led Géolocation to deploy it in many projects recently.
This technology dates back from several decades and these tools are known as terrestrial LiDAR (Light Detection and Ranging). Few scanners are based on the « Time of flight » principle which is simply the accurate measuring of the total travel time of laser from the sensor to the target. It allows for great range and excellent accuracy. More recently, the « Phase shift » principle has emerged, which is the measuring of the phase shift between the emitted and the received signal. Today we favor this last theory for the great speed of acquisition of point clouds.
Data acquisition with terrestrial LiDAR
During the acquisition of point clouds, we place the 3D scan at a fixed location in space and then record data along a 360 ° rotation. As some details may not be visible from this first point of view, we have to repeat the operation by moving the device according to several set up. In this way, we will acquire a faithful 3D representation of the area of interest. The main challenge then consists of assembling each point cloud into a master one. When 3D scans are performed indoors, it’s very accurate to use common walls to tie those scans together. For outdoor purpose, we work with stick-on, magnetic or even fixed and anchored targets. This combination provides a clear advantage if further stakeout is planned, because the checkpoints are already materialized.
Unleach the potential!
3D scans’ main advantage is definitely their fast acquisition capacity at very high density. This results in a point cloud dense enough to precisely draw architectural elements in 3D. Therefore, once the data collection is completed and controlled, processing and modeling id realized directly on the screen. Thus, we have in hands a planning and monitoring tool which is relevant at each step of the process. In other words, this technology allows a client to reduce design costs and increase efficiency! For example, we can thus produce a linearity analysis o along horizontal and vertical axes, even for complex elements. Applications are numerous, such as:
- Road works (creation of surfaces, topographic plans, deformation analysis, etc.)
- Volumetry (calculation of quantities, etc.)
- Industrial (bridge cranes, furnaces, as-built plan of industrial elements, etc.)
- Structures (accurate positionning validation)
- Architecture (interior design plan, facade of building in 3D mesh, accurate windows positionning, etc.)
- Maintenance (monitoring of deplacement (4D approach), etc.)
3D scanning and drawing in the point cloud allow us to produce topographic plans. The 3D data is also perfectly integrated into Civil3D and AutoCad. The acquisition of topographic elements is now carried out more efficiently from the point cloud, which reduces time in the field. In light of the above, the miscellaneaous applications of 3D scans become clearly obvious.
Géolocation team is always ready to take on new challenges. So feel free to contact our team of professionals in 3D scanning for the deployment of this technology in your projects! All this, obviously under the immediate supervision of a land surveyor, the measurement expert.
Curious to know more about it? Other applications of terrestrial LiDAR are available here.